1. Field of the Invention
The present invention relates to a walking type of electric lawn mower designed so that a cutter, accommodated in a cutter housing, is driven by an electric motor.
2. Description of the Related Art
U.S. Pat. No. 5,402,626 discloses an electric lawn mower including a single battery disposed at the rear of an electric motor which is mounted at a substantially central portion on a cutter housing. French Patent No. 2,039,175 discloses an electric lawn mower, including an electric motor mounted on a cutter housing in a rear of a rotational axis of a cutter, and a pair of batteries mounted on the cutter housing between the rotational axes of the electric motor and the cutter.
In the electric lawn mower disclosed in U.S. Pat. No. 5,402,626, a scroll portion, sloped up rearwards on the right of the electric motor, is provided on the cutter housing having a shape that widens rearwardly to relatively enlarge the area of a discharge port. The single battery, having an attitude extending in a longitudinal direction of the electric lawn mower, is disposed in a rear of the electric motor in such a manner as to avoid the scroll portion at a location offset leftwards from a straight line extending in the longitudinal direction of the electric lawn mower through the axis of the electric motor. Therefore, a space above the cutter housing in a rear of the electric motor is required for disposition of a battery having an attitude extending in the longitudinal direction of the electric lawn mower. Hence, the longitudinal length of the cutter housing is relatively increased. Since the battery, having a relatively large weight, is disposed offset leftwards on the cutter housing, the lateral weight balance of the cutter housing is non-uniform. If a pair of batteries are mounted on the cutter housing of the electric lawn mower disclosed in U.S. Pat. No. 5,402,626 in order to increase electric power capacity, the lateral weight balance of the cutter housing is further non-uniform, resulting in a reduced travelability of the electric lawn mower.
In the electric lawn mower disclosed in French Patent No. 2,039,175, the pair of left and right batteries are mounted on the cutter housing in front of the electric motor. With such an arrangement, the lateral weight balance of the cutter housing is substantially uniform. However, the arrangement is such that power from the electric motor is transmitted to the cutter through a power transmitting means such as a transmitting belt. Hence, a space at a central portion of the cutter housing is required for disposition of a driven pulley which is connected to a rotary shaft of the cutter housing. Therefore, the cutter housing must be relatively large-sized.